When to plant roses?

marylpn(6)November 23, 2010

I live in central PA and would love to order and plant the Knockout Rose so that it blooms next summer. Is it ok to plant at this time of year? I have heard different opinions, one says wait until winter when the plant is dormant another says wait till spring. Would appreciate any advise on this.

I haven't gardened in central PA, but I grew roses in the Philadelphia area, and also got my bachelor's degree in horticulture at the Main Campus of Penn State (and also lived in State College for about a year and a half after I graduated), so I'm not completely unfamiliar with the climate.

There are others on this forum who do grow roses in central PA (& similar areas in neighboring states). My climate north of Boston is probably similar in temperature to yours as far as winter cold goes, and approximately when the killing frosts hit.

I can only speak for myself. Having said that, in your shoes I'd wait to plant your rose until next spring, maybe a week or two after the Forsythia start blooming.

The good thing about the Knockout roses is that they're often pretty forgiving about how they're handled. Even so, if I lived in central PA and was going to plant (or transplant) a rose in the autumn I think I'd much prefer to do it between mid-September and Halloween. After that I think it probably gets too cold for the rose to settle in well before winter.

If you do plant it in the spring you'll need to make sure it gets enough water during those first months in the ground, and if you have a droughty summer (as often happens) you'll also need to keep an eye on its watering needs during that summer.

Adding one or two inches of a good mulch above the ground around the newly planted rose (but leaving a circle of bare soil extending out a few inches from where the new stems emerge from the soil) will help enormously with all of that.

If a dormant grafted plant you can plant as soon as the soil can be worked. Just cover the graft and canes with soil to protect fron a late freeze and drying out. If a growing bush in bud and bloom, wait until mid april at the earliest.

Do you have a potted plant? If so, plant it in the garden--that's the safest course. Plant so the graft swelling is just below soil level.

Are you thinking about ordering a plant? If so, the safest course is to wait until spring. Order bare root plants for delivery in mid- or late March, plant them then, and mound soil over the canes. Or, buy a leafed-out potted plant after danger of 27 degrees is past (probably late April in your area).

It is a good idea to prepare the soil now as the spring soil may be too wet to work.